<!DOCTYPE html>
<html>

	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>

	<body>
		<div class="box">
			月亮之上
		</div>
	</body>

</html>

<style type="text/css">
	body {
		background: url(img/img.jpg)no-repeat;
	}
	
	.box {
		width: 200px;
		height: 200px;
		margin: 50px;
		color: #fff;
		text-align: center;
		line-height: 200px;
		/* 给边框设置透明背景 */
		/*background: gray;*/
		background: rgba(0,0,0,0.3);
		
	}
</style>